Thats the same study we were talking about.
They are being a bit loose with their numbers. If you eliminate the outlier (which isn't readily justifiable), and if you round 47 up to 50 then you get a 50% reduction.
In order to be accurate, you should go to the actual paper and the data included rather than a reference in the text of another paper without all the relevant context.
As I clearly pointed out originally, the reduction of 47% (after elimination of the outlier) was close. Rounding that up to 50 is a little iffy, or maybe they were referring to the reduction in the mean per person usage of 53% and they were rounding down. The absolute reduction of opioids in the cited study was 24% with all participants included, 47% with outlier excluded.